Characterization, lateral variability and lateral extent of discontinuity surfaces on a Carbonate Platform (Barremian to Lower Aptian, Oman)

• Published in: Sedimentology 2005-04, Vol.52 (2), p.339-361
• Main Authors: SATTLER, UTE, IMMENHAUSER, ADRIAN, HILLGÄRTNER, HEIKO, ESTEBAN, MATEU
• Format: Article
• Language: English
• Subjects: Carbonate platform; Cretaceous; discontinuity surface; Oman; subaerial exposure
• ISSN: 0037-0746; 1365-3091
• DOI: 10.1111/j.1365-3091.2005.00701.x

Hiati of various duration in carbonates are commonly expressed as discontinuity surfaces. The understanding of processes that form and affect these surfaces leads to an improved sequence‐stratigraphic interpretation, a reliable outcrop correlation, and better models for reservoir compartmentalization. Various intraformational discontinuities were analysed and interpreted in a well‐exposed study window, 2·5 km in lateral length and 60 m in height comprising the Barremian‐Aptian Qishn Formation (Haushi‐Huqf area, central Oman). This study focuses on the lateral extent and morphology of the surfaces, the petrography of the underlying rocks, and the facies changes and geochemical trends across these discontinuities. Furthermore, the lateral variability of discontinuity surfaces was documented. Three genetic types of discontinuities are differentiated: (i) erosion surfaces; (ii) omission surfaces (hard‐ and firmgrounds); and (iii) composite surfaces with evidence for both subaerial exposure and submarine boring. Field observations, combined with petrographic and geochemical data, suggest that 17 surfaces are laterally extensive for at least 20 km and record relative sea‐level fluctuations of regional scale. In contrast, a large number of laterally limited surfaces (